Cyclists in Midtown “routinely disobey” traffic laws, ignore red lights, bike against traffic, and use iPods or Bluetooth devices while weaving around cars and pedestrians, a Hunter College study found.

A team of professors and students watched 5,275 cyclists at 45 intersections between First and 10th avenues and between 59th and 14th streets in April, and were shocked by the lawlessness on the streets.

“Cyclists should receive instruction on the rules of the road,” said study co-author Peter Tuckel. “Cyclists, along with drivers and pedestrians, have to be more mindful of the presence of the others.”

At least 37 percent of riders blew right past red lights, while 13.2 percent bucked traffic and 8.3 percent were yapping on a phone or jamming to an iPod, the study says.

Also, a careless 29.3 percent of the bikers in the study didn’t even use a nearby bike lane, and 75 percent of all bikers didn’t use headlights or taillights during evening hours — a clear violation of state law, the study found.

Some cyclists didn’t deny their bad behavior; they said biking allows them to skirt the normal rules of the road.

“Bicycling is something that lets you get away with a lot of recklessness on the road, which is fun,” said Piotr Redlinski, 37. “It should be tolerated, because the guys who run the red lights are skillful enough to do it safely.”

The report’s authors are calling for increased police enforcement of bike rules, and are also asking that people who bike for commercial purposes, such as messengers, get registered and have license plates.

But cycling advocates dismiss the study’s findings, pointing out “several major flaws” that cause it to “border on irrelevance.”

“They virtually excluded most of the bike lanes in the network. The 640-block area of Midtown has only six bike lanes,” said Wiley Norvell of Transportation Alternatives.

Also, he said, the researchers — many of them students — weren’t able to determine between a commercial or everyday rider.

Different laws apply to each — commercial cyclists have to have their company name displayed on the top part of their clothing, for example.